Stream capture, river capture, river piracy or stream piracy is a
geomorphological
Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or n ...
phenomenon occurring when a stream or river
drainage system or
watershed
Watershed is a hydrological term, which has been adopted in other fields in a more or less figurative sense. It may refer to:
Hydrology
* Drainage divide, the line that separates neighbouring drainage basins
* Drainage basin, called a "watershe ...
is diverted from its own bed, and flows instead down the bed of a neighbouring stream. This can happen for several reasons, including:
*
Tectonic
Tectonics (; ) are the processes that control the structure and properties of the Earth's crust and its evolution through time. These include the processes of mountain building, the growth and behavior of the strong, old cores of continents k ...
earth movements, where the slope of the land changes, and the stream is tipped out of its former course
*Natural
damming
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...
, such as by a
landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of ...
or
ice sheet
In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are in Antarctica and Greenland; during the Last Glacial Period at Las ...
*
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distin ...
, either
**
Headward erosion
Headward erosion is erosion at the origin of a stream channel, which causes the origin to move back away from the direction of the stream flow, lengthening the stream channel.Essentials of Geology, 3rd Ed, Stephen Marshak It can also refer to ...
of one
stream valley upwards into another, or
**Lateral erosion of a
meander
A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank ( cut bank) and deposits sediments on an inner, convex bank ...
through the higher ground dividing the adjacent streams.
**Within an area of
karst topography
Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...
, where streams may ''sink'', or flow underground (a sinking or
losing stream
A losing stream, disappearing stream, influent stream or sinking river is a stream or river that loses water as it flows downstream. The water infiltrates into the ground recharging the local groundwater, because the water table is below the bo ...
) and then reappear in a nearby stream valley
*Glacier retreat
The additional water flowing down the capturing stream may accelerate
erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distin ...
and encourage the development of a
canyon
A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tenden ...
(gorge).
The now-dry valley of the original stream is known as a
wind gap
A wind gap (or air gap) is a gap through which a waterway once flowed that is now dry as a result of stream capture. A water gap is a similar feature, but one in which a waterway still flows. Water gaps and wind gaps often provide routes which ...
.
Capture mechanisms
Tectonic uplift
*
Barmah Choke
Barmah is a town in the state of Victoria, Australia.
Barmah has the distinction of being located north of the border with the state of New South Wales. New South Wales is north of Victoria, with the border being the westward-flowing Murray Ri ...
: About 25,000 years ago, an uplift of the plains near Moama first dammed the
Murray River
The Murray River (in South Australia: River Murray) (Ngarrindjeri: ''Millewa'', Yorta Yorta: ''Tongala'') is a river in Southeastern Australia. It is Australia's longest river at extent. Its tributaries include five of the next six longest r ...
and then forced it to take a new course. The new course dug its way through the so-called Barmah Choke and captured the lower course of the
Goulburn River
The Goulburn River, a major inland perennial river of the Goulburn Broken catchment, part of the Murray-Darling basin, is located in the alpine, Northern Country/North Central, and Southern Riverina regions of the Australian state of Victoria. ...
for .
*
Barrier Range
A barrier or barricade is a physical structure which blocks or impedes something.
Barrier may also refer to:
Places
* Barrier, Kentucky, a community in the United States
* Barrier, Voerendaal, a place in the municipality of Voerendaal, Netherla ...
: The original course of the Murray River was to a mouth near
Port Pirie
Port Pirie is a small city on the east coast of the Spencer Gulf in South Australia, north of the state capital, Adelaide. The city has an expansive history which dates back to 1845. Port Pirie was the first proclaimed regional city in South ...
where a large delta is still visible protruding into the calm waters of
Spencer Gulf
The Spencer Gulf is the westernmost and larger of two large inlets (the other being Gulf St Vincent) on the southern coast of Australia, in the state of South Australia, facing the Great Australian Bight. It spans from the Cape Catastrophe and ...
. An uplift of the land blocked the river near the southern end of the
Flinders Ranges
The Flinders Ranges are the largest mountain range in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna.
The Adnyamathanha people are the Aboriginal group who have inhabi ...
, and the river eventually found its way to a new mouth near
Lake Alexandrina.
*
Indus
The Indus ( ) is a transboundary river of Asia and a trans-Himalayan river of South and Central Asia. The river rises in mountain springs northeast of Mount Kailash in Western Tibet, flows northwest through the disputed region of Kashmir, ...
-
Sutlej
The Sutlej or Satluj River () is the longest of the five rivers that flow through the historic crossroads region of Punjab in northern India and Pakistan. The Sutlej River is also known as ''Satadru''. It is the easternmost tributary of the Ind ...
-
Sarasvati
Saraswati ( sa, सरस्वती, ) is the Hindu goddess of knowledge, music, art, speech, wisdom, and learning. She is one of the Tridevi, along with the goddesses Lakshmi and Parvati.
The earliest known mention of Saraswati as a god ...
-
Yamuna
The Yamuna (Hindustani language, Hindustani: ), also spelt Jumna, is the second-largest tributary river of the Ganges by discharge and the longest tributary in List of major rivers of India, India. Originating from the Yamunotri Glacier at a ...
: The Yamuna earlier flowed into the
Ghaggar-Hakra River
The Ghaggar-Hakra River is an intermittent river in India and Pakistan that flows only during the monsoon season. The river is known as Ghaggar in India, before the Ottu barrage, and as the Hakra in Pakistan, downstream of the barrage, ending ...
(identified with the Sarasvati River) and later changed its course due to plate tectonics. The Sutlej River flowed into the current channel of the Ghaggar-Hakra River until the 13th century after which it was captured by the Indus River due to plate tectonics.
[K.N. Dikshit, 2013]
Origin of Early Harappan Cultures in the Sarasvati. Valley: Recent Archaeological Evidence and Radiometric Dates
Journal of Indian Ocean Archaeology, pp88-
Glacial damming
*The
River Thames
The River Thames ( ), known alternatively in parts as the The Isis, River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the Longest rivers of the United Kingdom, se ...
in southern
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...
originally entered the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
near
Ipswich
Ipswich () is a port town and borough in Suffolk, England, of which it is the county town. The town is located in East Anglia about away from the mouth of the River Orwell and the North Sea. Ipswich is both on the Great Eastern Main Line r ...
. About 450,000 years ago, an
ice sheet
In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are in Antarctica and Greenland; during the Last Glacial Period at Las ...
expanding from the north pushed the course of the river southwards, forcing the Thames to cut a new mouth where the mouth of the
River Blackwater, Essex
The River Blackwater is a river in Essex, England. It rises as the River Pant in the northwest of the county, just east of Saffron Walden, and flows in a generally southeast direction to Bocking, near Braintree, via Great Sampford and Great Ba ...
now is, north of London. It later moved southwards again to its current position as a result of cutting through the
Chiltern Hills
The Chiltern Hills is a chalk escarpment in England.
The area, northwest of London, covers stretching from Goring-on-Thames in the southwest to Hitchin in the northeast - across Oxfordshire, Buckinghamshire, Hertfordshire, and Bedfordshire. ...
at
Goring-on-Thames
Goring-on-Thames (or Goring) is a village and civil parish on the River Thames in South Oxfordshire, England, about south of Wallingford and northwest of Reading. It had a population of 3,187 in the 2011 census, put at 3,335 in 2019. Goring ...
, an event which created the
Goring Gap
The Goring Gap is the narrow valley, occupied by the River Thames, between the Chiltern Hills and the Berkshire Downs. It is approximately upstream of Reading and downstream of Oxford. The river here delimits Berkshire from Oxfordshire. The vil ...
.
Headward erosion
*The
Teays River
The Teays River
(pronounced taze) was a major preglacial river that drained much of the present Ohio River watershed, but took a more northerly downstream course. Traces of the Teays across northern Ohio and Indiana are represented by a network ...
, captured by the
Ohio River
The Ohio River is a long river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing southwesterly from western Pennsylvania to its mouth on the Mississippi River at the southern tip of Illino ...
.
*The
Rio Grande
The Rio Grande ( and ), known in Mexico as the Río Bravo del Norte or simply the Río Bravo, is one of the principal rivers (along with the Colorado River) in the southwestern United States and in northern Mexico.
The length of the Rio G ...
which before capture flowed into a
closed basin
An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes ...
,
Lake Cabeza de Vaca, but after capture flowed into the
Gulf of Mexico
The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...
.
*The ancestral
Niger River
The Niger River ( ; ) is the main river of West Africa, extending about . Its drainage basin is in area. Its source is in the Guinea Highlands in south-eastern Guinea near the Sierra Leone border. It runs in a crescent shape through ...
captured what is now the upper reaches of the Niger which once flowed into an
endorheic basin
An endorheic basin (; also spelled endoreic basin or endorreic basin) is a drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but drainage converges instead into lakes ...
to the east northeast of
Timbuktu
Timbuktu ( ; french: Tombouctou;
Koyra Chiini: ); tmh, label=Tuareg, script=Tfng, ⵜⵏⴱⴾⵜ, Tin Buqt a city in Mali, situated north of the Niger River. The town is the capital of the Tombouctou Region, one of the eight administrativ ...
.
*The
River Stour, Kent
The River Stour is a river in Kent, England that flows into the North Sea at Pegwell Bay. Above Plucks Gutter, where the Little Stour joins it, the river is normally known as the Great Stour. The upper section of the river, above its confluenc ...
, largely captured by the
River Beult
The River Beult ( ) is a tributary of the River Medway in South East England.
Course
The Beult has several sources west of Ashford, including one at Woodchurch. It then flows through Headcorn. At Hunton, above Yalding, it is joined by the ...
,
River Teise
The River Teise ( , ) is a tributary of the River Medway in Kent, England.
Course
The source of the Teise is in Dunorlan Park in Tunbridge Wells. From there the river flows eastwards past Bayham Abbey and then through Lamberhurst. downstream ...
and others.
*The
River Wey
The River Wey is a main tributary of the River Thames in south east England. Its two branches, one of which rises near Alton in Hampshire and the other in West Sussex to the south of Haslemere, join at Tilford in Surrey. Once combined the f ...
, in southern England, the western arm of which is the former upper waters of the
River Blackwater (River Loddon)
The River Blackwater is a tributary of the River Loddon, Loddon in England and sub-tributary of the River Thames, Thames. It rises at two springs in Rowhill Nature Reserve between Aldershot, Hampshire and Farnham, Surrey. It curves a course nor ...
.
*The
River Rheidol
The Afon Rheidol is a river in Ceredigion, Wales, in length. The source is Plynlimon. Receiving an average annual rainfall of , Plynlimon is also the source of both the Wye and the Severn.
Geography and geology
The Rheidol rises in the headw ...
in
Wales
Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...
which has captured the headwaters of other streams and now runs for part of its length in a deep gorge.
*The
River Lyd in
Devon
Devon ( , historically known as Devonshire , ) is a ceremonial and non-metropolitan county in South West England. The most populous settlement in Devon is the city of Plymouth, followed by Devon's county town, the city of Exeter. Devon is ...
, England.
*The Black River, in
Kings County, Nova Scotia
Kings County is a county in the Canadian province of Nova Scotia. With a population of 62,914 in the 2021 Census, Kings County is the third most populous county in the province. It is located in central Nova Scotia on the shore of the Bay of Fundy, ...
, Canada, captured by the
Gaspereau River
The Gaspereau River is a river in Kings County, Nova Scotia, Canada.
It has a length of approximately 24 km from its source at Gaspereau Lake on the South Mountain south of Kentville to its mouth at Hortonville on the Minas Basin. The lowe ...
*The
Casiquiare canal
The Casiquiare river () is a distributary of the upper Orinoco flowing southward into the Rio Negro, in Venezuela, South America. As such, it forms a unique natural canal between the Orinoco and Amazon river systems. It is the world's largest r ...
is a
distributary
A distributary, or a distributary channel, is a stream that branches off and flows away from a main stream channel. Distributaries are a common feature of river deltas. The phenomenon is known as river bifurcation. The opposite of a distributar ...
of the
Orinoco River
The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...
that is currently in the process of capturing the upper reaches of the Orinoco.
Karst
*The ''Donauversickerung'' (
Danube Sink), currently developing in
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
, where a large portion of the upper part of the
Danube
The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , pa ...
river sinks into the
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
bedrock, and resurfaces in the
Aachtopf
The Aachtopf () is Germany's biggest karst spring, south of the western end of the Swabian Jura near the town of Aach. It produces an average of 8,500 litres per second. Most of the water stems from the River Danube where it disappears undergro ...
spring
Spring(s) may refer to:
Common uses
* Spring (season), a season of the year
* Spring (device), a mechanical device that stores energy
* Spring (hydrology), a natural source of water
* Spring (mathematics), a geometric surface in the shape of a ...
, a tributary of the River
Rhine
), Surselva, Graubünden, Switzerland
, source1_coordinates=
, source1_elevation =
, source2 = Rein Posteriur/Hinterrhein
, source2_location = Paradies Glacier, Graubünden, Switzerland
, source2_coordinates=
, so ...
.
Glacier retreat
The
Slims River
The Slims River (Ä’äy Chù) was a glacially fed river in the Canadian territory of Yukon. Until 2016, it originated in the Kaskawulsh Glacier, then ran approximately 15 mi (24 km) into the southern terminus of Kluane Lake.
Over the ...
was previously fed by
meltwater
Meltwater is water released by the melting of snow or ice, including glacial ice, tabular icebergs and ice shelves over oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reducing. Meltwater can be ...
from the
Kaskawulsh Glacier in the
St. Elias Mountains
The Saint Elias Mountains (french: Chaîne Saint-Élie) are a subgroup of the Pacific Coast Ranges, located in southeastern Alaska in the United States, Southwestern Yukon and the very far northwestern part of British Columbia in Canada. The range ...
in the
Yukon
Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...
and its waters flowed into
Kluane Lake
Kluane Lake is located in the southwest area of the Yukon. It is the largest lake contained entirely within Yukon at approximately , and long.
Kluane Lake is located approximately northwest of Haines Junction. The Alaska Highway follows most of ...
and on to the
Bering Sea
The Bering Sea (, ; rus, Бе́рингово мо́ре, r=Béringovo móre) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasses on Earth: Eurasia and The Ameri ...
. Because of
climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
, the glacier has rapidly receded and the meltwater no longer feeds the Slims. The water instead now feeds the Kaskawulsh River which is a tributary to the
Alsek River
The Alsek River (; Tlingit ''Aalseix̱' '') is a wilderness river flowing from Yukon into Northern British Columbia and into Alaska. It enters the Gulf of Alaska at Dry Bay.
Most of the Alsek River's basin is within protected wilderness areas an ...
and drains into the
Gulf of Alaska
The Gulf of Alaska (Tlingit: ''Yéil T'ooch’'') is an arm of the Pacific Ocean defined by the curve of the southern coast of Alaska, stretching from the Alaska Peninsula and Kodiak Island in the west to the Alexander Archipelago in the east, ...
.
Effect on freshwater life
River capture is a shaping force in the
biogeography
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, ...
or distribution of many
freshwater
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include ...
fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
species.
[Albert, J. S., Schoolmaster, D. R., Tagliacollo, V., & Duke-Sylvester, S. M. (2016). Barrier displacement on a neutral landscape: Towards a theory of continental biogeography. Systematic Biology, syw080]
Australian freshwater fish
The formerly massive
Great Dividing Range
The Great Dividing Range, also known as the East Australian Cordillera or the Eastern Highlands, is a cordillera system in eastern Australia consisting of an expansive collection of mountain ranges, plateaus and rolling hills, that runs rough ...
runs the length of the eastern coastline of Australia and has isolated native freshwater fish populations east and west of the range for millions of years. In the last two million years erosion has reduced the Great Dividing Range to a critical point where west-to-east river capture events have been possible. A number of native fish species that originated in the Murray–
Darling river system to the west are (or were) found naturally occurring in a number of coastal systems spanning almost the entire length of the range.
None of the river capture events that allowed native fish of the Murray-Darling system to cross into and colonise these East Coast river systems seem to have formed permanent linkages. The colonising Murray-Darling fish in these East Coast river systems have therefore become isolated from their parent species, and due to isolation, the
founder effect
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. It was first fully outlined by Ernst Mayr in 1942, using ...
,
genetic drift
Genetic drift, also known as allelic drift or the Wright effect, is the change in the frequency of an existing gene variant (allele) in a population due to random chance.
Genetic drift may cause gene variants to disappear completely and there ...
and
natural selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Charle ...
, have become separate species (see
allopatric speciation
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from ...
).
Examples include:
*
Golden perch
The golden perch (''Macquaria ambigua'') is a medium-sized, yellow or gold-coloured species of Australian freshwater fish found primarily in the Murray-Darling River system, though a subspecies is found in the Lake Eyre-Cooper Creek system, an ...
(
Dawson–
Fitzroy Fitzroy or FitzRoy may refer to:
People As a given name
*Several members of the Somerset family (Dukes of Beaufort) have this as a middle-name:
**FitzRoy Somerset, 1st Baron Raglan (1788–1855)
** Henry Charles FitzRoy Somerset, 8th Duke of Beau ...
river system, central
Queensland
)
, nickname = Sunshine State
, image_map = Queensland in Australia.svg
, map_caption = Location of Queensland in Australia
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, established_ ...
).
*
Eel-tailed catfish
The eel-tailed catfish, ''Tandanus tandanus'', is a species of catfish (order Siluriformes) of the family Plotosidae. This fish is also known as dewfish, freshwater catfish, jewfish, and tandan.
This species is a freshwater fish native to th ...
(several rivers, northern
New South Wales
)
, nickname =
, image_map = New South Wales in Australia.svg
, map_caption = Location of New South Wales in AustraliaCoordinates:
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, es ...
). However, note recent genetic research which now indicates eel-tailed catfish colonised east coast drainages in multiple colonisation events relatively recently (by evolutionary standards) and may subsequently have colonised the Murray–Darling system via an east-to-west river capture event, contrary to usual west-to-east capture events listed here.
*
Macquarie perch
The Macquarie perch (''Macquaria australasica'') is an Australian native freshwater fish of the Murray-Darling river system. It is a member of the family Percichthyidae and is closely related to the golden perch (''Macquaria ambigua'').
The ...
(
Hawkesbury Hawkesbury or Hawksbury may refer to:
People
*Baron Hawkesbury, or Charles Jenkinson, 1st Earl of Liverpool (1727-1808), English statesman
Places
;Geography
*Hawkesbury Island, an island in British Columbia, Canada
* Hawkesbury Island, Queensland ...
-
Nepean
Nepean may refer to:
Places Australia
*Nepean Bay, a bay in South Australia,
**Nepean Bay Conservation Park, a protected area in South Australia,
**Nepean Bay, South Australia, a locality
*Nepean Highway, Victoria
*Nepean Island (Norfolk Island) ...
rivers,
Shoalhaven River
The Shoalhaven River is a perennial river that rises from the Southern Tablelands and flows into an open mature wave dominated barrier estuary near Nowra on the South Coast of New South Wales, Australia.
Location and features
The Shoalhaven ...
, southern New South Wales).
*
River blackfish
The river blackfish (''Gadopsis marmoratus'') is a freshwater fish endemic to the temperate waters of south-eastern Australia. It is found from southern Queensland through to central Victoria, including in the Murray- Darling river system. It ...
(multiple rivers,
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
).
*
Murray cod, whose eastern species/subspecies are:
**
Eastern freshwater cod
The eastern freshwater cod (''Maccullochella ikei''), also known as the eastern cod or Clarence River cod, is a large predatory freshwater fish of the genus ''Maccullochella'' and the family Percichthyidae, that occur in the coastal Clarence Rive ...
(
Clarence River system, northern New South Wales. It was also found in the
Richmond River
The Richmond River is a river situated in the Northern Rivers region of New South Wales, Australia.
Course and features
The river rises at the northern end of the Richmond Range, near its junction with the McPherson Range, on the Queensla ...
system in New South Wales but that population is now extinct.)
**
Brisbane River cod
The Brisbane River cod was a unique form of ''Maccullochella'' cod that occurred naturally in the Brisbane River system, an east coast river system in south east Queensland, Australia. The Brisbane River Cod was known as the Bumgur (meaning blu ...
(
Brisbane River
The Brisbane River is the longest river in South East Queensland, Australia, and flows through the city of Brisbane, before emptying into Moreton Bay on the Coral Sea. John Oxley, the first European to explore the river, named it after the Go ...
system, southern Queensland. That population is now extinct, and its exact taxonomic status is not known.)
** The
Mary River cod
The Mary River cod (''Maccullochella mariensis'') is a species of temperate perch native to the coastal Mary River (Queensland), Mary River system of southern Queensland, Australia. Mary River cod are one of Australia's most endangered freshwa ...
(
Mary River, southern/central Queensland.)
* The
mountain galaxias
''Galaxias olidus'', the mountain galaxias, is a species of freshwater galaxiid fish widely found in southeastern Australia.
Description
As for other members of the species complex, although ''Galaxias olidus'' exhibits a greater range of charac ...
species complex
In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...
(multiple rivers, southern Queensland, New South Wales, Victoria).
Olive perchlet (''Ambassis agassizii''),
western carp gudgeon
The western carp gudgeon (''Hypseleotris klunzingeri'') is one of several carp gudgeon species. Carp gudgeons are very small perciform fish (similar in size, shape and colour) found in the Australian Murray River, Murray-Darling River system, m ...
(''Hypseleotris klungzingeri''), pygmy perch (''Nannoperca australis'') and
Australian smelt
The Australian smelt (''Retropinna semoni'') is a small, pelagic silvery freshwater fish found in large numbers in waters of the south eastern Australian mainland.
Distribution
The fish is endemic to Australia and widely distributed through the ...
(''Retropinna semoni'') also appear to have made crossings into coastal systems, the last two species seemingly many times as they are found in most or all coastal streams in south eastern Australia as well as the
Murray-Darling system.
Unfortunately, with the exception of
eastern freshwater cod
The eastern freshwater cod (''Maccullochella ikei''), also known as the eastern cod or Clarence River cod, is a large predatory freshwater fish of the genus ''Maccullochella'' and the family Percichthyidae, that occur in the coastal Clarence Rive ...
and
Mary River cod
The Mary River cod (''Maccullochella mariensis'') is a species of temperate perch native to the coastal Mary River (Queensland), Mary River system of southern Queensland, Australia. Mary River cod are one of Australia's most endangered freshwa ...
, it has not been widely recognised that these coastal populations of Murray–Darling native fish are separate species and their classifications have not been updated to reflect this. Many are threatened and two, the
Richmond River cod and the
Brisbane River cod
The Brisbane River cod was a unique form of ''Maccullochella'' cod that occurred naturally in the Brisbane River system, an east coast river system in south east Queensland, Australia. The Brisbane River Cod was known as the Bumgur (meaning blu ...
, have become extinct.
See also
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Lake capture
In geology, lake capture is the process of capture (see Stream capture) of the waters collected in a lake by a neighbor river basin.
The occurrence of a lake capture is mainly controlled by the water balance at the lake's basin and the changes in ...
*
Niger River
The Niger River ( ; ) is the main river of West Africa, extending about . Its drainage basin is in area. Its source is in the Guinea Highlands in south-eastern Guinea near the Sierra Leone border. It runs in a crescent shape through ...
*
Misfit stream
A misfit stream is a river that is either too large or too small to have eroded the valley or cave passage in which it flows. This term is also used for a stream or river with meanders that obviously are not proportional in size to the meanders ...
References
{{DEFAULTSORT:Stream Capture
Rivers
Biogeography
Fluvial geomorphology
Hydrology